Placer deposits form when heavy eroded particles settle out of moving water hot, metal-rich fluids cool below the surface magma cools in underground chambers organic matter is compressed over millions of years

heavy eroded particles settle out of moving water

Placer deposits forms when rocks weathered due to the effect of water. The heavy minerals from the rocks get settled down in water. Minerals that form placer deposits  have high specific gravity, they are resistant to chemical weathering process and are durable.

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